Hi guys

Does anybody have a how to thread on x300 sovereign 4.0 gearbox removal can it be taken out on its own?

Any help would be great I couldn't find d a link anywhere

 

I haven't seen that, but you can download the repair manual from several sources on line.

 

Cheers thanks do u know if can be taken out without taking out the engine with it?

 

I just checked my repair manual which is from the Jaguar Heritage Trust. There was lots of service info, and some limited instructions on removing the engine/transmission as a unit but that's all. I think it would be possible since it can be done on the XJ8, but can't help beyond that.

One of the more experienced members will hopefully see your thread and assist.

 

Hi damotron,

On the late XJ40s that use the same ZF 4HP24 gearbox, it can be removed without removing the engine.

I haven't done it myself, but if I recall correctly, the central section of the exhaust system must be removed, and of course the transmission mount/rear engine mount.

Once the driveshaft is disconnected from the transmission it may also be necessary to disconnect the driveshaft center bearing in order to move the driveshaft sufficiently out of the way. Don't disconnect the bearing from the bracket. Instead, mark the position of the bracket on the underbody before removing the four screws that secure it to the body so you can return it to its exact location.

Other things that need to be disconnected include the transmission cooler lines, dipstick tube, electrical connector(s) and rotary switch cable.

You will probably need to support the rear end of the engine, but you will also probably have to let the engine tilt somewhat in order to access all of the bell housing bolts. It may be possible to reach the top ones along the firewall if you have some long box-end wrenches or other suitable tools.

I think the reason there is so little info on removing the XJ40 and X300 transmission is that the AJ6/AJ16 engines and ZF 4HP24 transmissions have proven to be so bullet-proof. Very few owners have had to drop the gearbox. If I may ask, what is prompting you to drop yours?

Cheers,

Don

 

Hi don thanks for info

Basically took to shop as when i put into any gear park neutral reverse or drive it makes a hydraulic groaning noise a very loud one then when the car shifts from 1st to second and 2nd to 3rd it makes a very quick blip of a groan. Also when decelerating you can hear a faint humming/spinning noise. Im guessing its torque convertor as gearbox oil is nice and pink and smells sweet and when driving the car shifts smoothly theres no hesitation at all no fault codes either. Its a 1995 sovereign 4.0 litre. The noise os coming from the front of gearbox around bellhousing area.

 

What kind of fluid is in the transmission?

In our '93, I used Dexron VI for awhile because the bottle said it was backward compatible in gearboxes for which Dexron III was originally specified (all licenses for Dexron III expired at the end of 2006 so it hasn't been available since then). On my next fluid change I did some research and discovered that the viscosity index of Dexron VI (and most other newer transmission fluids) is significantly lower than the original Dexron III.

At the recommendation of a friend on the Jag-Lovers forum, I looked into Redline Oil D4 ATF and learned that its viscosity index is very similar to Dexron III, so I gave it a try and it completely transformed our transmission. I hadn't realized that while using Dexron VI the torque converter was never fully locking up. The difference was obvious, and the car now shifts better, accelerates better, engine-brakes better while descending hills, and there is a much more noticeable difference in Sport Mode with the transmission holding lower gears coming out of curves, etc.

If a modern low-VI fluid is currently in your transmission, I would suggest a drain and refill with Redline D4 ATF. It may solve the problem and would be a lot less expensive than any mechanical work on the transmission.

Cheers,

Don

 

Yes its just got valvolineatf designed to meet most gearbox specs but my car has shifted smooth and great the whole time only does the loud hydraulic groan when stopped and putting shifter into another position thinking its the torque convertor bolt/s shedded or something of the sort as there was a hell of a bang under feet and we didnt run anything over and thetes no fluid leaking

 

We'll be anxious to hear what you find out. When you're putting it back together, I would recommend you consider refilling with the Redline D4 ATF, which has a kinematic viscosity of 34 at 40C. For comparison, the kinematic viscosity at 40C of Valvoline Maxlife is just 28.8 - low even by modern standards and much too low for our older gearboxes.

Please keep us informed.

Don

 

I will definitely let u know my findings however thats interesting i have ordered the redline d4 atf like you advised. If i was to flush old stuff out with that could i then reusr fluid if it still makes noise and decide just change box over as the fluid alone is costing me 306nzd.

Also i fpu d a gearbox in a xj40 ate they same as x300 just a straight swapover?

 

Not all XJ40s used the ZF 4HP24 electronic-controlled gearbox, but the '93-'94 4.0L cars do. I don't know if there are any differences in the electrical connector or connection for the cable at the rotary switch. The Transmission Control Modules are different, but I assume the X300 TCM can run a late XJ40 gearbox if the electrical connector at the gearbox matches.

Hopefully someone will reply with a definitive answer.

Cheers,

Don

 

I checked torque convertor bolts today appear to be tight but sound definitely company ng from that area sounds mechanical like a is line spinning not grabbing properly maybe something is broken off in there

 

Please keep us informed damotron.

Cheers,

Don